About PropSims

PropSims is a free-beta website that publishes NFL and NBA fantasy projections, DFS tools and player-prop simulations, all built from its own game-simulation model.

What PropSims does

For every NFL game of the week, Thursday through Monday, we simulate the whole game 10,000 times, both offenses together, and read each player's numbers off the results. Instead of a single projection, every player gets a range: a median, a floor (10th percentile) and a ceiling (85th percentile). The same simulations power everything on the site (how the simulations work):

Props board: our simulated median and probability against posted player-prop lines, for sportsbooks and pick'em apps.
Start/Sit assistant and Ask the sims: compare players head-to-head in PPR, half-PPR or standard.
Season-long and weekly rankings by position, with floors and ceilings.
DFS projections, a lineup optimizer and a Showdown optimizer for FanDuel and DraftKings.
A news feed that re-runs a game when an injury changes and shows what moved.
NBA projections from a separate model, in beta for the 2026-27 season.
A public track record of every graded prop forecast.

Free beta

PropSims is in a free beta with no card required. A paid tier may come later. If anything changes, it will be announced first, and beta users will hear about it before anyone else. Bulk CSV downloads need a free newsletter signup; everything else is open on the site.

Who it's for

Season-long fantasy managers deciding who to start, with ranks in full PPR (our default), half-PPR and standard. See PPR vs half-PPR vs standard.
DFS players on FanDuel and DraftKings who want salary, value and ceiling in one place. See free DFS projections and floor and ceiling explained.
Player-prop bettors (21+) who want a model probability to compare with the line, along with an honest record of how that model has done.

How we work

Own model only. Everything on the site is our model's output. We don't blend in or republish other sites' projections.
No hand edits. Nobody adjusts a single player's projection. If a number looks wrong, we fix the model or its inputs, and the fix applies to everyone.
Logged before kickoff. Every prop forecast is written to an append-only, hash-chained log before the game and graded afterwards against the official box score. Picks are never removed or re-priced after the fact.
Honest about limits. We make no win-rate claims. Our backtests, including the parts that don't flatter us, are on the methodology page.
Open data sources. Play-by-play and box scores come from nflverse (CC-BY 4.0). Prop lines are shown only from sources that permit display.

Not to be confused with

PropSims (propsims.com) is a sports projections site. It is not affiliated with:

PropSim or other prop-trading tools, trading simulators or prop-trading firms. PropSims has nothing to do with funded trader programs or financial markets.
Keysight PROPSIM, Keysight's radio channel emulation product.
The NFL, the NBA, FanDuel, DraftKings, Underdog, PrizePicks or any sportsbook.

Responsible gaming

PropSims is for entertainment and informational purposes only. It is not betting advice, there is no guarantee of results, and you must be 21+ (or the legal age where you live). If gambling stops being fun, call 1-800-GAMBLER. See our terms and privacy.

Follow and contact

Follow @PropSims on X, join the PropSims Discord, or get the free weekly email. Questions about the numbers? Start with the FAQ and the glossary.